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Abstract  

A new convenient method has been proposed to synthesize mixed-ligand -diketonato Tc(III) complexes, using the ligand exchange reaction [Tc(acac)2(CH3CN)2]++L [Tc(acac)2L]+ +2CH3CN where L is bza, dpm or dbm. The yield was about 30–40%. UV-visible and IR spectra of these complexes were measured. Characteristic features of the compounds were compared with those of the corresponding complexes of ruthenium.

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Abstract  

Solvent extraction of microamounts of cesium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B) in the presence of dodecaethylene glycol (DDEG, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, H2L2+, CsL+ and CsHL2+ (L = DDEG) are extracted into the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene saturated with water have been determined.

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Abstract  

Extraction of microamounts of barium by a nitrobenzene solution of ammonium dicarbollylcobaltate (NH4 +B-) in the presence of 15-crown-5(15C5,L) has been investigated. The equilibrium data have been explained assuming that the complexes NH4L+, NH4L2 + and BaL2 2+ are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined.

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Abstract  

The complexes of the general formula MLSCN (M=Cu(I), Ag(I), L=2,2′-bipyridine=2-bipy, 4,4′-bipyridine=4-bipy or 2,4′-bipyridine=2,4′bipy) have been prepared and their IR spectra examined. The nature of metal-ligand coordination is discussed. Thermal decomposition in air of these complexes occurred in several successive endothermic and exothermic processes and the residue was Cu2O and Ag, respectively.

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Abstract  

This paper deals with the investigation concerning the thermal stability of two new azo-derivatives and their Cu(II) complexes of type [Cu(L1)2] and, respectively, ((C4H9)4N)2[Cu(L2)2]. The thermal decomposition steps have been put in evidence. For the kinetically workable ones, the values of the activation energy vs. conversion degree were determined.

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Acta Botanica Hungarica
Authors: C. Çi̇rak, M. Odabaş, A. Ayan, B. Sağlam, and K. Kevseroğlu

The genus Hypericum has attracted scientific interest for recent years, since it is a source of a variety of compounds including hypericin. The present study was conducted out to develop leaf area prediction models for some Hypericum species containing hypericin, namely H. pruinatum, H. perfoliatum, H. aviculariifolium subsp. depilatum var. depilatum (endemic), H. montanum, H. montbretii, H. linarioides, H. triquetrifolium, H. bithynicum and H. perforatum growing wild in Northern Turkey. Lamina width, length and leaf area were measured without destroying to develop the models. The actual leaf areas of the plants were measured by Placom digital planimeter, and multiple regression analysis with Excel 7.0 computer package program was performed for the plants separately. The produced leaf area prediction models in the present study were formulised as LA = (a) + (b 1 × L) + [b 2 × (L × W)] + (b 3 × L 2 ) + (b 4 × W 2 ) + [b 5 × (L × W 2 ] + [b 6 × (L 2 × W)] + [b 7 × (L 2 + W 2 )] where LA is leaf area, Wis leaf width, L is leaf length and a, b 1 , b 2 , b 3 , b 4 , b 5 , b 6 , and b 7 are coefficients. R 2 values varied with species from 0.80 in H. aviculariifolium subsp. depilatum var. depilatum to 0.97 in H. pruinatum . All R 2 values and standard errors were found to be significant at the p < 0.001 level.

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Abstract  

The investigations concerning the thermal behaviour of a series of Ni(II) and Cu(II) complexes of type [NiLCl2mH2O ((1) L:L1, m=6; (3) L:L2, m=4) or [CuLCl]nCln·mnH2O ((2) L:L1, m=6; (4) L:L2, m=4) are presented. The ligands L(1) and L(2) have been synthesised by template condensation of 3,6-diazaoctane-1,8-diamine or 1,2-diaminoethane with formaldehyde and 2-amino-4H-1,2,4-triazole. The bonding and stereochemistry of the complexes have been characterised by IR, electronic and magnetic studies at room temperature. The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity against planktonic as well as biofilm embedded Gram-negative, Gram-positive and fungal strains. The thermal behaviour provided confirmation of the complexes composition as well as the number and nature of water molecules and the intervals of thermal stability.

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Abstract  

Mn(II), Co(II), Ni(II) and Cu(II) complexes having the general composition M(L)2X2 [where L = 2-pyridinecarboxaldehyde semicarbazone, M = Mn(II), Co(II), Ni(II) and Cu(II), X = Cl and NO3 ] have been synthesized. All the synthesized compounds were identified and confirmed by elemental analysis, molar conductance, magnetic susceptibility measurements, mass, IR, EPR, electronic spectral studies and thermogravimetric analysis (TG). The Molar conductance measurements of the complexes lie in the range 209–228 Ω1 cm−1 mol−1 indicating that the complexes are 1:2 electrolytic in nature. Thus the complexes may be formulated as [M(L)2]X2. The magnetic moment measurements of the complexes indicate that all the complexes are in high-spin state. On the basis of spectral studies an octahedral geometry has been assigned for Mn(II), Co(II) and Ni(II) complexes whereas tetragonal geometry for Cu(II) complexes. The thermal studies suggested that the complexes are more stable compared with free ligand. This fact was supported by calculating the thermodynamic parameters by using Horowitz–Metzger (HM) and Coats–Redfern (CR) equations. The free ligand and its metal complexes were also evaluated against the growth of phytopathogenic fungi and bacteria in vitro.

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Abstract  

New mixed-ligand complexes with empirical formulae M(4-bpy)L21.5H2O (M(II)=Mn, Co), Ni(4-bpy)2L2 and Cu(4-bpy) L2H2O (where: 4-bpy=4,4'-bipyridine, L=CC L2HCOO-) have been isolated in pure state. The complexes have been characterized by elemental analysis, ir spectroscopy, conductivity (in methanol, dimethylformamide and dimethylsulfoxide solutions) and magnetic and x-ray diffraction measurements. The Mn(II) and Co(II) complexes are isostructural. The way of metal-ligand coordinations discussed. the ir spectra suggest that the carboxylate groups are bonded with metal(II) in the same way (Ni, Cu) or in different way (Mn, Co). The solubility in water is in the order of 19.4010-31.8810-3ł mol dm-3ł. During heating the hydrate complexes lose all water in one step. The anhydrous complexes decompose to oxides via several intermediate compounds. A coupled TG-MS system was used to analyse the principal volatile products of obtained complexes. The principal volatile products of thermal decomposition of complexes in air are: H2O2 +, CO2 +, HCl+, Cl2 +, NO+ and other.

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Abstract  

Let G denote a locally compact abelian group and H a separable Hilbert space. Let L p(G, H), 1 ≤ p < ∞, be the space of H-valued measurable functions which are in the usual L p space. Motivated by the work of Helgason [1], Figa-Talamanca [11] and Bachelis [2, 3], we have defined the derived space of the Banach space L p(G, H) and have studied its properties. Similar to the scalar case, we prove that if G is a noncompact, locally compact abelian group, then L p 0(G, H) = {0} holds for 1 ≤ p < 2. Let G be a compact abelian group and Γ be its dual group. Let S p(G, H) be the L 1(G) Banach module of functions in L p(G, H) having unconditionally convergent Fourier series in L p-norm. We show that S p(G, H) coincides with the derived space L p 0(G, H), as in the scalar valued case. We also show that if G is compact and abelian, then L p 0(G, H) = L 2(G, H) holds for 1 ≤ p ≤ 2. Thus, if FL p(G, H), 1 ≤ p < 2 and F has an unconditionally convergent Fourier series in L p-norm, then FL 2(G, H). Let Ω be the set of all functions on Γ taking only the values 1, −1 and Ω* be the set of all complex-valued functions on Γ having absolute value 1. As an application of the derived space L p 0(G, H), we prove the following main result of this paper. Let G be a compact abelian group and F be an H-valued function on the dual group Γ such that

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\sum \omega (\gamma )F(\gamma )\gamma$$ \end{document}
is a Fourier-Stieltjes series of some measure µ ∈ M(G, H) for every scalar function ω such that |ω(γ)| = 1. Then Fl 2(Γ, H).

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